#include "common.h"

ListNode* mergeTwoLists(ListNode* list1, ListNode* list2)
{
	if (list1 == NULL)
	{
		return list2;
	}
	else if (list2 == NULL)
	{
		return list1;
	}
	if (list1->val < list2->val)
	{
		list1->next = mergeTwoLists(list1->next, list2);
		return list1;
	}
	else
	{
		list2->next = mergeTwoLists(list2->next, list1);
		return list2;
	}
}